Beginner

Suited for a wide range of uses, Level 1 Beginner telescopes are simple to operate and set up. Some initial assembly may be required. Very good optical and mechanical quality. Great for families, young people, and folks who don't want to mess with equipment but just want to take a look. Any of these scopes will show you countless lunar craters, Saturn's rings and a myriad of star clusters and nebulas! Referring to the manual is recommended.

With its substantial 90mm (3.5") aperture and versatile f/7.3 optics, the StarBlast 90mm Travel Refractor is the great grab-and-go telescope you've been looking for. Not only will you get great views of the Moon and its hundreds of intriguing craters and canyons, but this compact travel telescope will also provide awesome views of comets, Jupiter's cloud bands, the four largest Jovian moons, and Saturn's amazing ring system, even from brighter urban locations.

Since the StarBlast 90mm is so portable and lightweight at 13.5 lbs. when fully assembled, it's easy to take on the road to your favorite dark sky site, or bring along on the next family campout or road-trip. From reasonably dark skies, this portable performer grabs very nice views of emission nebulas like the Lagoon (M8), the Orion Nebula (M42), as well as dying stars like the Ring Nebula (M57), globular clusters like the Great Cluster in Hercules (M13), and gorgeous open star clusters like the Double Cluster in Perseus and the glittering Pleiades (M45). From a dark sky site with inky black skies, there are literally hundreds of deep sky objects you can track down with the affordable StarBlast 90mm Travel Refractor Telescope and a star chart of astronomy program such as the included free special edition of Starry Night.

The included altazimuth mount is easy to operate, and gives the StarBlast 90mm telescope a stable foundation. The mount's convenient slow-motion controls make it easy to manually track celestial objects as you view them over extended periods.

This portable performer comes with a host of great astronomy accessories. The StarBlast 90mm Travel Refractor includes a 90° star diagonal for comfortable nighttime viewing, a 25mm eyepiece for 26.4x views, 10mm eyepiece for more powerful 66x views, an EZ Finder II reflex sight to help aim the refractor, and free Starry Night Special Edition astronomy software.

For optional use during the day, you can use a 90° 1.25" Correct-Image Star Diagonal (#8787, sold separately) to have the StarBlast 90mm Refractor display a correctly oriented, non-reversed daytime view. (The included star diagonal yields an image that is upright, but reversed left-to-right). Not compatible with correct image diagonals #7216 or #8754.

Limited Warranty against defects in materials or workmanship for one year from date of purchase. This warranty is for the benefit of the original retail purchaser only. For complete warranty details contact us at 800-676-1343.

User level

Level 1 Beginner - Suited for a wide range of uses, these telescopes are simple to operate and set up. Some initial assembly may be required. Very good optical and mechanical quality. Great for families, young people, and folks who don't want to mess with equipment but just want to take a look. Any of these scopes will show you countless lunar craters, Saturn's rings and a myriad of star clusters and nebulas! Referring to the manual is recommended.

Level 2 Intermediate - These scopes offer higher performance and more advanced features than Level 1: Beginner models. They typically take a bit longer to learn and need some set-up or adjustments. But anyone with the slightest technical bent will have no problem getting familiar with these models. Referring to the manual is recommended.

Level 3 Advanced - These scopes provide the best performance but may require more skill to master and appreciate. They have exceptionally fine optics and mechanics. Some are easy to use but are but on the large or heavy side. Some are intended for specialized uses. These scopes will appeal to the more technically inclined. Referring to the manual is highly recommended.

Level 4 Expert - Expert telescopes offer uncompromising optical and mechanical quality for the most demanding amateur astronomer. They may be technically involved or designed for specialized use, such as astrophotography or detailed deep sky observation. They carry a premium price, but are designed to provide the ultimate performance in the field. Referring to the manual is highly recommended.

Optical design

Reflector telescopes use a pair of large and small mirrors to direct incoming light to the eyepiece.
Refractor telescopes refract, or "bend" incoming light to a focus by means of an objective lens.
Cassegrain telescopes, such as Maksutov-Cassegrains, "fold" incoming light using two mirrors and a front "corrector" lens.

Optical diameter

For telescopes, the optical diameter (also known as aperture) is the size of a telescope's main light-collecting lens or primary mirror, measured in millimeters or inches. Telescopes with larger optical diameters collect more light, which leads to an increase in brightness and image resolution compared to smaller instruments.

For binoculars, the optical diameter (also known as objective lens diameter) is the size of each of the front-facing objective lenses of a binocular measured in millimeters. Binoculars with larger objective lenses collect more light, which increases image resolution and brightness. Binoculars with larger objective lenses are recommended for low light situations, and binoculars with at least 50mm or larger objective lenses are recommended for pleasing astronomical observations at night.

Focal length

The distance from the center of a curved mirror or lens at which parallel light rays converge to a single point. The focal length is an inherent specification of a mirror or lens and is one of the factors in determining resultant magnification for a telescope (along with the focal length of the eyepiece being used).

Focal ratio

The focal ratio of an optical system is the ratio of a telescope's focal length to its aperture. Short focal ratios (f/5, f/4.5) produce wide fields of view and small image scales, while long focal lengths produce narrower fields of views and larger image scales.

Coatings

Binocular lenses and prisms are often coated with anti-reflective material to minimize light loss as light travels through the multiple optical surfaces of a typical binocular. Coatings help maximize the amount of light transmitted through each glass surface of a binocular, so as much light as possible reaches the observer's eyes to provide a bright and sharp image.

Good lenses are at least "fully coated," with a single layer of magnesium fluoride coating applied to each air-to-glass lens surface. Multiple layers of coatings are even more effective; the term "multi-coated" means one or more air-to-glass lens surface has multiple coatings. "Fully multi-coated" optics are even better, meaning all lens surfaces have multiple layers of anti-reflective coatings applied for maximum light transmission and optimal image quality.

Optics type

Newtonian reflectors will have either a spherical shaped mirror, which is less expensive to produce, or a higher quality parabola, which does not result in spherical aberration. Cassegrain telescopes routinely use spheres in addition to other lenses in the optical path to correct for residual spherical aberration.
Refractors use a series of lenses to provide a clear image. Designs range from a standard air-spaced doublet (two lenses in a row) to exotic designs such as oil-spaced triplets and 4-element multi group lenses.

Glass material

Refractors use glass lenses to focus the light, and the glass material plays an important role in the quality of the resulting image. Standard achromatic refractors routinely use Crown and Flint for the two elements, but more expensive apochromatic refractors can use ED (extra low dispersion) glass for one or more of the lenses. Reflector mirrors are made from glass with different levels of thermal expansion. Standard mirrors are made from material such as Soda-Lime Plate glass and BK-7 glass. Glass with Pyrex or other low thermal expansion material will not change shape as dramatically during the cool-down period, resulting in more stable images during this period.

Resolving power

The theoretical resolving power of a telescope can be calculated with the following formula: Resolving power (in arc seconds) = 4.56 divided by aperture of telescope (in inches). In metric units, this is: Resolving power (in arc seconds) = 116 divided by aperture of telescope (in millimeters). Note that the formula is independent of the telescope type or model, and is based only upon the aperture of the telescope. So the larger the telescope's aperture, the more it is capable of resolving. This is important to keep in mind when observing astronomical objects which require high resolution for best viewing, such as planets and double stars. However, it is usually atmospheric seeing conditions (not the telescope) which limits the actual resolving power on a given night; rarely is resolution less than one arc-second possible from even the best viewing locations on Earth.

Lowest useful magnification

Lowest useful magnification is the power at which the exit pupil becomes 7mm in diameter. Powers below this can still be reached with the telescope to give wider fields of view, but the image no longer becomes brighter at a lower power. This is due to the fact that the exit pupil of the telescope (the beam of light exiting the eyepiece) is now larger than the average person's dark adapted pupil, and no more light can fit into the eye.

Highest useful magnification

The highest practical limit is different from the often used "highest theoretical magnification" specification. The "theoretical" limit generally is 50x the aperture of the scope in inches (2x the aperture in mm). So for example, an 80mm refractor is capable of 160x, and a 10" telescope is theoretically capable of 500x magnification.
But after approximately 300x, theory breaks down and real world problems take over. The atmosphere above us is constantly in motion, and it will distort the image seen through the telescope. This effect may not be noticeable at lower powers, but at higher powers the atmosphere will dramatically blur the object, reducing the quality of the image. On a good night (a night where the air above is steady and the stars aren't twinkling), the practical upper limit of a large telescope is 300x, even thought the theoretical limit may be much higher. This doesn't mean the scope will never be able to reach those higher "theoretical" powers - there will be that rare night where the atmosphere is perfectly still and the scope can be pushed past it's practical limit, but those nights will be few and far between.

Limiting stellar magnitude

Astro-imaging capability

The astro-photographic capability of the telescope is based on the style, stability, and accuracy of the mount and tripod. Telescopes on either very lightweight mounts or non tracking mounts (such as Dobsonians) are capable of only very short exposures such as lunar photographs. If a motor drive is attached to an equatorial mount, even a small lightweight mount is capable of capturing some planetary detail. Larger EQ mounts that utilize very precise tracking and excellent stability are capable of longer exposure deep-sky photography.

Height range of mount

The height range specification is a measure of the tripod itself - not the eyepiece height. Since telescopes come in all shapes and sizes, the eyepiece height will vary, even when using the same tripod. For an EQ tripod the mount is set up so the counterweight shaft is horizontal, and then the height is measured from the ground to the center of the mounting plate.

Warranty

This warranty gives you specific legal rights. It is not intended to remove or restrict your other legal rights under applicable local consumer law; your state or national statutory consumer rights governing the sale of consumer goods remain fully applicable.

Orders received by 1pm Eastern Time for in-stock items ship the same business day. Orders received after 1pm will ship the next business day. When an item is not in-stock we will ship it as soon as it becomes available. Typically in-stock items will ship first and backordered items will follow as soon as they are available. You have the option in check out to request that your order ship complete, if you'd prefer.

With its substantial 90mm (3.5") aperture and f/7.3 optics, the StarBlast 90mm Refractor is the great grab-and-go telescope you've been looking for. This value-packed kit comes with a Shorty 2x Barlow and the Orion Beginning Stargazer's Toolkit.

Having trouble viewing details on the Moons surface? This neutral-density eyepiece filter reduces glare so you can see more detail and surface features. The 1.25" Orion 13% Transmission Moon Filter is especially useful with large aperture telescopes.

The affordable MoonMap 260 is a must-have for any backyard astronomer. The laminated map includes both a correct and reversed view of the Moon and identifies over 260 popular lunar features including craters, valleys, mountain ranges, and more!

Need for a good way to start identifying constellations? The Orion Star Target Planisphere is the perfect telescope accessory! Designed for 30-50 deg North latitude and includes simple instructions and viewing tips. Just dial in the date and time!

You've just bought your first telescope, but now what? The Orion Beginning Stargazer's Toolkit is the perfect addition! This best selling kit includes a planisphere star atlas, Discover the Stars book, Orion MoonMap 260, and a red flashlight.

A great tool for bringing out details in the planets and Moon is this 1.25" set of four Orion Color Telescope Filters. Each colored filter brings out different details in the planets allowing for a totally different view.

Orion Sirius Plossl eyepieces are ideal for any type of telescope, refractor, reflector, or catadioptic. They offer a 52° field with clean, high-contrast images. All air-to-glass surfaces are fully coated for improved light transmission.

The Orion DualBeam LED Astro Flashlight is a great multipurpose flashlight that lets you choose red or white light with the flip a switch. Red light preserves your night vision, while white light is brighter and great for packing up after viewing.

For cleaning the lenses in your telescope or binocular, the Orion Microfiber Optics Cleaning Cloth lifts dirt, fingerprints, water and oil from surface without scratching, streaking or smearing delicate lens surfaces. The cloth is machine washable.

At Orion, we are committed to sharing our knowledge and passion for astronomy and astrophotography with the amateur astronomy community. Visit the Orion Community Center for in-depth information on telescopes, binoculars, and astrophotography. You can find astrophotography "how to" tips and share your best astronomy pictures here. Submit astronomy articles, events, and reviews, and even become a featured Orion customer!